Lamp jrase



Jan. 24, 1956 TAMIS 2,732,532

LAMP BASE LEAD-IN CONNECTION Filed Dec. 28, 195:5

Imam/ 72i? 6 6025 614. Ta /rials 6 WW2," ri M dig 2151 LAMPABA'SE George A. Tamls,IiNdl|ant, Mns.,atfigndr to Consolidated Electric vLamp Company, Lynn, .Mass a corporation of Massachusetts Application December- 28, msa sennm. pom-s62 1' Claim. (c1. 2.39am

This invention relates to the basing of lamps, as for example of the incandescent electric type, andhas for its principal object the provision of a lamp base and method of manufacture by which the lead wire of a lamp may, without the use of solder, be conveniently and effectively electrically connected to the end of the lamp base, thereby to facilitate and to effect economy in the basing operation.

Other objects of the invention are to provide a lamp base of the type described which is of simple and durable construction, efficient in operation, economical to manufacture and attractive in appearance.

In one aspect the invention involves a lamp base comprising an apertured end, a contact plate fast to the end and having a mouth, and a lead wire extending outwardly through the aperture of the base end and into the mouth, the mouth having a lip under lateral compression and the edge of which is in clamping engagement with the wire. The mouth may have aplurality of lips under lateral compression, the edges of which are in clamping engagement with the wire.

In another aspect the lamp comprises a tipof insulation, a contact disk having circumferentially spaced inwardly extending prongs embedded in the tip and having a mouth, and a lead wire extending outwardly through the aperture of the tip and into the mouth, the mouth having a lip under lateral compression and the edge of which is in clamping engagement with the wire. The disk may have a plurality of circumferentially spaced slots extending laterally from the mouth to form a plurality of lips.

In another aspect the invention involves the method of connecting a lead wire to a contact plate at the apertured base end of a lamp which comprises the steps of forming a mouth and lip in the plate, and threading the lead wire through the aperture of the base end and into the mouth and into clamping engagement with the edge of the lip.

In another aspect the method comprises the steps of forming the mouth with a protrusion comprising an outwardly projecting lip, threading the lead wire through the aperture of the base end and through the mouth and pressing the lip inwardly to bring the edge of the lip into clamping engagement with the lead wire. The protrusion and outer end of the wire may be reduced substantially to the plane of the outer face of the plate. Further, the lead wire may be extended outwardly beyond the lip and the extended end is severed prior to pressing the lip inwardly.

In still another aspect the invention involves a stage porduct for use in the practice of the method comprising a lamp base having an apertured end, a contact plate fast to the end and having a mouth formed with an outwardly projecting lip bendable inwardly to close the month about the lead wire.

For the purpose of illustration a typical embodiment of the invention is shown in the accompanying drawings in which Fig. 1 is a side elevation of one form of contact 2,732,532 Ratented Jan. 24 .1956

plate used .in the present invention .and before assembly with the body .of the lamp base;

Fig. 2 is a top plan view of the contactplate of Fig. .1;

Fig. 5 is aside elevation of the lamp -.base with the contact plate .of Fig. :1 assembled therewith and ready :to ;receive *a lead wire;

Fig. 4 is a'view similar to :Fig. 3 withpartshown in central vertical section and with a lead wire :shown in position to be connected to the :base;

Fig. Sis-a fragmentary view :similar toFig. 4with the extended end of "the wire .removed; and

Fig-x6 is .a iviewssimila-r .to Fig. 5 after the :lead wire has been "connected .to the lhase.

With reference to Figs. 3 and 4 of the drawings, the lamp base comprises an externally threaded sheet metal shell 1 having one end enclosed with a ring 2 of insulation as for example glass, constituting a tip of insulation having a central aperture 3 communicating with the interior of the shell.

A contact plate 4, preferably in the form of a disk, is mounted on the tip and is provided with circumferentially spaced inwardly extending prongs 5 which extend into the tip and are embedded therein to hold the contact plate fast to the tip.

By suitable means, as for example a conventional die punch, the plate is formed with a central opening or mouth 7 and with a plurality of slots 8 extending laterally and radially from the center to form a plurality of lips 9, the lips being inclined outwardly and in converging relation to each other to constitute a protrusion above the plane of the face of the plate (Figs. 1 and 2). When the plate is mounted on the tip as aforesaid, the mouth is in registry with the aperture 3 of the tip.

In the basing operation and with the contact plate assembled with the tip as above described and as shown in Fig. 4 with respect to the plate of Fig. l, the lead wire 10 of a conventional incandescent lamp (not shown) is threaded through the aperture 3 of the tip and through the mouth 7 of the contact plate (Fig. 4), the outer or extended end 11 of the wire projecting outwardly beyond the outer edge of the lips. The extended end of the wire may then be severed adjacent said outer edge of the lips as shown in Fig. 5 in any convenient manner as by cutting with shears or by breaking off against the edges of one of the slots 8.

With the wire thus positioned the lips are pressed or bent inwardly by suitable means as a conventional hollow presser foot to close the mouth 7 about the wire and to bring the outer protruding edges of the lips into engagement with the wire, the lips during this pressing operation being placed under lateral compression and in clamping engagement with the wire. The protrusion may then be reduced substantially to the plane of the outer face of the plate as shown in Fig. 6 in any suitable manner, as for example by rolling, grinding or pressing the same inwardly or cutting off an outerportion of the protrusion and then rolling or pressing the protrusion inwardly.

From the foregoing it will be understood that the invention involves a circumferential shell such as 1, a ring of insulation such as 2 fast to the tip end of the shell with its aperture approximately coaxial with the shell, and a contact plate such as 4 mounted on the ring in a plane extending transversely of the axis of the shell, the plate being cut to provide opposed lips 9 which are bent outwardly to provide a mouth 7 between their opposed edges, the mouth being in alignment with the aforesaid aperture so that a wire may be threaded through the aperture, thence through the mouth and then pinched between the aforesaid edges when the lips are bent back into the aforesaid plane; and in the preferred embodiment the plate is cut from the center outwardly in several directions to provide pointed lips whose tips substantially meet at the center when the lips are disposed in the aforesaid plane.

While in the foregoing description the steps of severing the extended end of the wire, and reducing the protrusion were described as performed successively, it is to be understood that said steps may be performed concomitantly with equal effect.

It should be understood that the'present disclosure is for the purpose of illustration only, and that this invention includes all modifications and equivalents which fall within the scope of the appended claim.

I claim: I

A lamp base comprising a circumferential shell, a ring of insulation fast to the tip end of the shell with its aperture approximately coaxial with the shell, a contact plate mounted on the outer end of the ring in a plane extending transversely of the axis of the shell, the plate being cut from the center outwardly in several directions to provide pointed lips, and a lead wire extending through said aperture into said plane, said lips lying in said plane with their edges abutting each other so as to close said end of the shell and with their pointed tips pinched against the lead wire from several directions firmly to hold the end of the wire in-said plane.

References Cited in the file of this patent UNITED STATES PATENTS 

